What are your top five favorite US cities?  Here are mine in no particular order:

1. Minneapolis - it's a homer choice, but I really love it here.  It's the laid back midwest feel with plenty of stuff to do.
2. Seattle - it's like a big city in northern Minnesota, except there's mountains. 
3. San Francisco - just like my home town, except the hills aren't as steep :) 
4. Santa Cruz - not a big city, but they have a beach and a boardwalk with a roller coaster.  Lots of camping nearby.   Pine trees and mountains (do you see a theme?)
5. Chicago - big city close to home.  It's just a lot of fun to visit.  Lots of food and places to go.

Runners up:

1. New York
2. Boston
3. Denver
4. Washington D.C.

Places I'd like to go to that I've never been to:

1. Dallas/Houston/San Antonio
2. Honolulu
3. New Orleans
4. Toronto (yes, it's not a US city)
5. San Diego

Places I'd like to go back to for further research:

1. New York
2. Philadelphia
3. Cleveland
4. Los Angeles